GB2047283A

GB2047283A - Housing for receiving a thread monitoring unit which comprises a thread tension sensor

Info

Publication number: GB2047283A
Application number: GB8012536A
Authority: GB
Original assignee: Schubert und Salzer Maschinenfabrik AG
Current assignee: Rieter Ingolstadt Spinnereimaschinenbau AG
Priority date: 1979-04-26
Filing date: 1980-04-16
Publication date: 1980-11-26
Also published as: US4300340A; IT8020759A0; IN152558B; GB2047283B; FR2455103B1; CH644160A5; DE7912192U1; CS215058B2; IT1130560B; FR2455103A1; HK42383A

Description

1 GB 2 047 283 A 1

SPECIFICATION Housing for receiving a thread monitoring unit, which comprises a thread tension sensor

This invention relates to a housing for adcommodating a thread monitoring unit, which 70 itself comprises a thread tensioning sensor, and a switching device for controlling a fibre feed device of an open-end spinning unit (station).

In a known apparatus an opening, serving for the through passage of thread drawn off from the spinning station, is provided in the cover of an open-end spinning unit or station (British Patent Application No. 7909488 Serial No. 2017169 and Schubert and Salzer brochure "Rotorspinner RU 11 /RU80"). In this opening is the thread tension sensor of a thread monitoring unit which, in dependence on the thread tension, controls a fibre feed device for the spinning unit. The thread monitoring unit is attached to the cover directly or with the interposition of a plate, which forms the cover of a housing which accommodates a spinning element. The fibre feed device may be controlled by means of a press button, which can be caused to act on the thread tension sensor and pivot the latter. This push button is either carried by the thread monitoring unit or is attached to the cover independently of the thread monitoring unit.

The attachment of these parts is effected by means of a number of screws. Installation of the thread monitoring unit is a time-consuming 95 matter, as the positioning of the thread monitoring unit relative to cover the is difficult.

Underlying the present invention is the object of so constituting the housing that it is functionally coordinated to the cover. For achieving this the 100 cover and the housing should be so coordinated to one another, through the shape given them, that assembly is facilitated. According to the invention it is arranged for the housing to have a first abutment element, which 105 receives the switching device, and a second abutment element for adjustment on a holder.

Associated with the two abutment elements are corresponding openings in the holder, with the result that the said abutment elements serve as an 110 adjusting device, which correctly determines the position and attitude of the housing. The attachment of the housing, whether this is effected directly or indirectly, that is to say by means of a connecting element, does not, therefore, present the slightest difficulty, and can therefore be rapidly effected.

Conveniently, for protecting the thread sensor, the second said abutment element accommodates the thread tension sensor, for which purpose this abutment element is in the form of two parallel ribs between which the thread tension sensor lies.

The thread monitoring unit can be constructed in a particularly spacesaving way if the thread tension sensor is rotatable about an axis. So that the path of rotary movement of the thread tension sensor may be limited, it is preferable if the ribs extend above the path of travel of the thread tension sensor, and are sufficiently close to one another to ensure that they form stops for limiting the path of travel of the thread tension sensor.

With a view to simplifying the attachment of the housing to the holder the second abutment element is constituted as a screw thread member by means of which the housing is attached to the holder. No further attachment means will then be required.

The invention is hereinafter further explained by reference to the accompanying drawings, in which:

Figure 1 shows part of the cover with the housing constituted according to the invention, and Figure 2 is a side elevational view of the housing, the side wall having been removed.

The spinning unit, which is constituted in the conventional way and of which Figure 2 only shows,the upper portion of the mouth of the thread draw-off tube 1, is screened, during the production of the thread 3, by a hinge-mounted cover 2. This cover comprises an opening 20 through which extend two parallel spaced ribs 60, which are positioned on either side of the path of thread travel; the side edges 22 of the opening 20 go fit neatly round the ribs 60.

The ribs are an integral component of a housing 4, which carries a switching device 5 which, in a known manner, is used for controlling a fibre feed device (not shown). The switching device 5 extends through an opening 21 in the housing 4; this opening 21 is so small that it closely surrounds the switching device 5. In this way the opening 20 and the opening 21 of the housing 4 satisfactorily determine the position and attitude (orientation) of the housing 4. This provision is of essential importance for satisfactory operation of the thread monitoring unit 6, which is accommodated in the housing 4, so that the thread tension force, required for actuating the thread monitoring unit 6, actually corresponds to that force which has been calculated to be necessary for such actuation of the thread monitoring unit 6. This is usually the case when the thread tensioning force is actually applied to the thread tension sensor 61 in the direction envisaged.

The installation of the housing 4 on the cover 2 has hitherto been a comparatively troublesome operation, as the threaded bores in the housing 4 and the corresponding holes in the cover 2 are relatively small and, also, the surfaces of the housing 4 and of the cover 2 are in mutual alignment without being capable of determining or controlling the relative positioning required. In contradistinction to this, the ribs 60 and the cooperating opening 20 in the cover 2 are of relatively great surface area, so that the ribs can easily be introduced into the opening 20. Attachment of the housing 4 to the cover 2 does not them present any difficulty, as the threaded bores in the housing 4 and the holes in the cover 2 - which are required for the necessary attachment - automatically assume the position of mutually aligned abutment by reason of the provision of the 2 GB 2 047 283 A abutment elements, which are provided for adjusting the mutual positioning of the housing and cover and which are constituted by the ribs 60 and by the switching device 5. Due to the provision of the ribs 60 and of the opening 20 which cooperates with these ribs, and also through the provision of the switching device 5 and of the opening 21 which cooperates with the latter, the housing 4 is functionally coordinated to the holder constituted by the cover 2.

In the embodiment illustrated the first of the said abutment elements of the housing 4 is in the form of two parallel ribs 60 between which the thread tension sensor 61 lies. The thread tension sensor 61 is thus protected from outside influences, so that unintended pivoting of the thread tension sensor 61 is prevented from occurring.

In the embodiment illustrated, the thread tension sensor 61 can turn about a pivot axis 62; the thread tension sensor 61 lies across the direction in which the thread tension acts. The pivot axis 62 is therefore positioned close to one of the ribs 60, while the free end of the thread tension sensor 61 abuts against the other rib 60 when no thread tension is being applied. Thus, this other rib 60 serves as a stop for limiting the path of movement.

When spinning is to be started, the thread tension sensor 61 is brougt into its position of readiness in which it lies against the rib 60 nearest its pivot axis 62, so that the sensor 61 does not then obstruct the thread draw-off tube 1, whereby the process of introducing the thread 3 into the thread draw-off tube 1 is appreciably assisted.

Thus, the rib 60 also serves as a stop for limiting the path of movement.

When thread tension is being applied, the thread tension sensor 61 is in its centre position, in which it does not touch either of the two ribs 105 60.

In order to ensure that the ribs 60 can actually serve as the said stop for limiting the required path of movement, these ribs 60 extend to a point lying above the path of movement of the thread tension 110 sensor 61 and are a corresponding distance apart from each other.

As, in addition to the guide means in the housing 4, additional guide means is usually required for switching device 5, the first of the said abutment elements, in the embodiment shown in the drawings, is so constituted that a screw thread member 50 is provided for the switching device 5, this screw thread member projecting through the cover 2 and being of sufficient strength to ensure that the housing 4 can be attached to the cover 2 by means of this screw thread device 50. In this way it is possible to dispense with the provision of separate attachment means in the form of screws, for which it wouId be necessary to provide.

additional screw threaded bores in the housing 4 and holes in. the cover 2. Accordingly, it is possible, by the provision of a screw thread on the switching device 5, further to functionally coordinate the housing 4 to the cover 2.

2 The invention has been described above by way of example with reference to the housing 4 of a thread monitoring unit 6, which is arranged on a cover 2 which screens the spinning unit or station.

However, it would be possible to replace the cover 2 by another form of holder for the housing 4; the particular nature of this alternative form of holder for the housing 4 will depend on the particular construction selected for the spinning apparatus.

In the embodiment explained with reference to the drawings, the second said abutment element is constituted by two parallel ribs 60 between which the thread tension sensor 61 lies. This form of construction is particularly advantageous.

However, it is also possible to arrange for the second abutment element to be constructed in some otherway, e.g. in the form of a PI-OleCtion of cylindrical or some ot ther shape.

With a view to rendering manufacture simple and economic the housing 4 is, advantageously, made of synthetic plastics materia'. This does not entail any problems as a rule because the switching device 5 and the thread monitoring unit 6 do notbecome heated in the course of their oparation. so that there is no accumulation of heat in the housing 4.

In addition to the thread monitoring unit 6, with ch,e thread tensioning sensor 61 and switching device 5, which serves to control the thread feed device (not shown), the housing 4 may also contain a control device 7 with further electrical elements, one or more of which evolves a particularly large amount of heat. For example, there is provided a repulsion magnet 70 which is J 00 approached, on the occurrence of a thread breakage, by a lug 63 of the thread tensioning sensor 6 1; this lug 63 is susceptible to magnetic effects. A contactless switch 71 is actuated, and interrupts the feed of fibres and also energizes the repulsion magnet 70, which pivots the thread tension sensor 61, immediately after the occurrence of a thread breakage, until this sensor 61 comes into abutment with one of the ribs 60. In this position the thread tension sensor 61 does not obstruct the mouth of the thread draw-off tube 1.

The repulsion magnet 70 evolves heat while it is in its energized condition. This heats the inside space of the housing 4 and may result in damage being caused to the repulsion magnet 70 or to other electrical elements 72 present in the housing 4.

The housing 4 consists of a plastics part 40, which contains an internal space 41 which accommodates the control device 7; however, with a view to preventing the parts mentioned in the previous paragraph from becoming damaged, the housing 4 has a metal carrier which is attached LO this plastics part 40 and which carries at least the elements of the control device 7 (e.g. the repulsion magnet 70) which evolve heat. In the embodiment illustrated, the metal carrier is in the form of a metal cover 42, and is integral with the latter. The heat evolved is immediately transferred to the metal cover 42, which dissipates this heat by radiation to the atmosphere 60 surrounding the cover 42. As shown in Figure 1, the metal cover 42 has, on its outside, blades 43 which serve to improve this dissipation of heat 5 through radiation.

The dissipation of heat is further improved if the 65 holder, e.g. the cover 2, consists of metal, and if the metal cover 42 has a section 44 which abuts this holder.

In order that the section 44 may abut in a particularly satisfactory manner against the 70 holder, which consists of metal, and also with a view to achieving particularly good dissipation of heat through the cover, the screw thread member 50 of the switching device 5 at least partially consists of metal, and this part of the screw thread member 50, which consists of metal, is connected to the metal cover 42 by way of a metal bridge 45.

The improved removal of heat occurs, in this case, as a result of the improved contact between the section 44 of the metal cover 42 and the holder, on the one hand, and, on the other hand, between the part of the screw thread member which is connected to the metal cover 42 and the holder.

This provision also improves the way in which the housing 4 is functionally coordinated to the holder.

However, the control device 7 may also 85 comprise further heat-evolving elements, e.g. a thyristor 73 which, for the sake of achieving a compact housing structure, may lie in a different plane, in the housing 4, from that of the repulsion magnet 70 (see Figure 2). In this case, the housing 90 4 has an intermediate plate 46 which, conveniently, niay be constituted in the form of a printed circuit and electrically connects together the electrical elements 72 and the thyristor 73. An attachment plate 47 for the thyristor 73 is connected to the metal cover 42 by way of a metal strip 48 which, in the embodiment illustrated, is an integral constituent of the metal cover 42, although it may be arranged to be separable from the metal cover 42 and/or from the 100 attachment plate 47. the heat evolved by the thyristor 73 is therefore conducted by way of the attachment plate 47 and the metal strip 48 to the metal cover 42 which, in the way described above, transmits the heat to the outside atmosphere or, 105 by way of the holder, to other parts of the machine.

As the previous description indicates, the housing may be modified in a large number of ways. The two abutment elements are used for 110 adjusting the housing 4 and, hence, the thread tensioning sensor 61. If the switching device simultaneously comprises a screw thread member 50, this screw thread member can be used as an attachment means for the housing 4 in addition to 115 its use as an adjUS'Li.,Ig means. Due to the fact that GB 2 047 283 A 3 the switching device 5 is equipped with a screw thread member 50 the way in which the housing abuts against the holder is improved. If the housing 4 has a metal cover 42 and, furthermore, if the holder is of metal, this form of construction enables heat to be dissipated in a particularly satisfactory way, although the housing 4 proper has a plastics material shell 40 which defines the internal space 5 1. In all the instances described above the housing 4 is functionally coordinated to the holder, which is for example constituted as the cover 2. In a preferred embodiment of the invention the side wall 49 of the housing 4 is constituted as a metal cover, which either replaces or is used in addition to the metal cover 42. This side wall 49 is also in contact with the metal carrier, which carries the heat-evolving elements 70 and 73. This form of construction affords the advantage that the air Pleated by the radiated heat rises on the outside of the side wall 49 as a result of which, in consequence of the air movement and of the air exchange, a particularly good dissipation of air is realized.. This air dissipation can be further accelerated by fixing the blades 43 on this side wall 49.

Claims

1. A housing for receiving a thread monitoring unit, which comprises a thread tensioning sensor, and a switching device for controlling a fibre feed device of an open-end spinning unit (station), characterized in that the housing comprises a first abutment element, which accommodates the switching device, and a second abutment element for adjustment on a holder.

2. A housing according to Claim 1 characterized in that the second stop abutment accommodates the thread tension sensor.

3. A housing according to Claim 2, characterized in that the second abutment element is in the form of two parallel ribs between which the thread tension sensor lies.

4. A housing according to Claim 3, in which the thread tension sensor is in the form of a rotary sensor which can turn about an axis, characterized in that the ribs extend above the path of movement of the thread tension sensor, and lie so close to one another that they form stops for limiting the path of travel of the thread tension sensor.

5. A housing according to any of Claims 1 to 4, characterized in that the first abutment element is constituted as a screw thread member for attaching the housing to the holder.

6. A housing for receiving a thread monitoring unit constructed substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1980. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies maybe obtained.